add version to sdist

(ve)merzky@thinkie:~/saga/saga-python/devel (devel *$%=) $ rm VERSION saga/VERSION
(ve)merzky@thinkie:~/saga/saga-python/devel (devel *$%=) $ rm -rf dist/
(ve)merzky@thinkie:~/saga/saga-python/devel (devel *$%=) $ python setup.py sdist | 0
(ve)merzky@thinkie:~/saga/saga-python/devel (devel *$%=) $ tar ztvf dist/saga-python-0.9.13.tar.gz | grep VERSION
-rw-r--r-- merzky/merzky     19 2013-12-10 23:55 saga-python-0.9.13/saga/VERSION
-rw-r--r-- merzky/merzky      6 2013-12-10 23:55 saga-python-0.9.13/VERSION
Merge branch 'devel' of github.com:saga-project/saga-python into devel